Answer / laxman rapolu

where as In UV-absorbance detection : absorbance of solute
less than that of mobile phase. It can be avoided by use of
mobile phase with lower UV absorbance

Answer / falguni patel

1. Difference in the composition of the sample and mob phase.
2. Often may sample contains extraneous ingredients such as excipients.
3. Sample may not exactly dissolve in mob phase.

Answer / ramakrishna,micro labs

Based on mobile phase negative peaks we observed,for ex: the mobile phase having TEA,Acetic acid or OPA (those all r used for mobile phase pH adjustment) .that type of chemicals will show negative response in HPLC

Answer / nisha

we show negative peak because of impurites

Answer / piysh

wrong dilution selection

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